src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
   4                   2000-2002 Guus Sliepen <guus@sliepen.warande.net>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: net_setup.c,v 1.1.2.5 2002/02/26 23:26:41 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <netdb.h>
  28 #include <netinet/in.h>
  29 #ifdef HAVE_LINUX
  30  #include <netinet/ip.h>
  31  #include <netinet/tcp.h>
  32 #endif
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <signal.h>
  37 #include <sys/time.h>
  38 #include <sys/types.h>
  39 #include <syslog.h>
  40 #include <unistd.h>
  41 #include <sys/ioctl.h>
  42 /* SunOS really wants sys/socket.h BEFORE net/if.h,
  43    and FreeBSD wants these lines below the rest. */
  44 #include <arpa/inet.h>
  45 #include <sys/socket.h>
  46 #include <net/if.h>
  47
  48 #include <openssl/pem.h>
  49 #include <openssl/rsa.h>
  50 #include <openssl/rand.h>
  51
  52 #include <utils.h>
  53 #include <xalloc.h>
  54 #include <avl_tree.h>
  55 #include <list.h>
  56
  57 #include "conf.h"
  58 #include "connection.h"
  59 #include "meta.h"
  60 #include "net.h"
  61 #include "netutl.h"
  62 #include "process.h"
  63 #include "protocol.h"
  64 #include "subnet.h"
  65 #include "graph.h"
  66 #include "process.h"
  67 #include "route.h"
  68 #include "device.h"
  69 #include "event.h"
  70
  71 #include "system.h"
  72
  73 char *myport;
  74
  75 int read_rsa_public_key(connection_t *c)
  76 {
  77   FILE *fp;
  78   char *fname;
  79   char *key;
  80 cp
  81   if(!c->rsa_key)
  82     c->rsa_key = RSA_new();
  83
  84   /* First, check for simple PublicKey statement */
  85
  86   if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key))
  87     {
  88       BN_hex2bn(&c->rsa_key->n, key);
  89       BN_hex2bn(&c->rsa_key->e, "FFFF");
  90       free(key);
  91       return 0;
  92     }
  93
  94   /* Else, check for PublicKeyFile statement and read it */
  95
  96   if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
  97     {
  98       if(is_safe_path(fname))
  99         {
 100           if((fp = fopen(fname, "r")) == NULL)
 101             {
 102               syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 103                      fname, strerror(errno));
 104               free(fname);
 105               return -1;
 106             }
 107           free(fname);
 108           c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 109           fclose(fp);
 110           if(!c->rsa_key)
 111             {
 112               syslog(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 113                      fname, strerror(errno));
 114               return -1;
 115             }
 116           return 0;
 117         }
 118       else
 119         {
 120           free(fname);
 121           return -1;
 122         }
 123     }
 124
 125   /* Else, check if a harnessed public key is in the config file */
 126
 127   asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 128   if((fp = fopen(fname, "r")))
 129     {
 130       c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 131       fclose(fp);
 132     }
 133
 134   free(fname);
 135
 136   if(c->rsa_key)
 137     return 0;
 138   else
 139     {
 140       syslog(LOG_ERR, _("No public key for %s specified!"), c->name);
 141       return -1;
 142     }
 143 }
 144
 145 int read_rsa_private_key(void)
 146 {
 147   FILE *fp;
 148   char *fname, *key;
 149 cp
 150   if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key))
 151     {
 152       myself->connection->rsa_key = RSA_new();
 153       BN_hex2bn(&myself->connection->rsa_key->d, key);
 154       BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 155       free(key);
 156       return 0;
 157     }
 158
 159   if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 160     asprintf(&fname, "%s/rsa_key.priv", confbase);
 161
 162   if(is_safe_path(fname))
 163     {
 164       if((fp = fopen(fname, "r")) == NULL)
 165         {
 166           syslog(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 167                  fname, strerror(errno));
 168           free(fname);
 169           return -1;
 170         }
 171       free(fname);
 172       myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 173       fclose(fp);
 174       if(!myself->connection->rsa_key)
 175         {
 176           syslog(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 177                  fname, strerror(errno));
 178           return -1;
 179         }
 180       return 0;
 181     }
 182
 183   free(fname);
 184   return -1;
 185 }
 186
 187 int check_rsa_key(RSA *rsa_key)
 188 {
 189   char *test1, *test2, *test3;
 190 cp
 191   if(rsa_key->p && rsa_key->q)
 192     {
 193       if(RSA_check_key(rsa_key) != 1)
 194           return -1;
 195     }
 196   else
 197     {
 198       test1 = xmalloc(RSA_size(rsa_key));
 199       test2 = xmalloc(RSA_size(rsa_key));
 200       test3 = xmalloc(RSA_size(rsa_key));
 201
 202       if(RSA_public_encrypt(RSA_size(rsa_key), test1, test2, rsa_key, RSA_NO_PADDING) != RSA_size(rsa_key))
 203           return -1;
 204
 205       if(RSA_private_decrypt(RSA_size(rsa_key), test2, test3, rsa_key, RSA_NO_PADDING) != RSA_size(rsa_key))
 206           return -1;
 207
 208       if(memcmp(test1, test3, RSA_size(rsa_key)))
 209           return -1;
 210     }
 211 cp
 212   return 0;
 213 }
 214
 215 /*
 216   Configure node_t myself and set up the local sockets (listen only)
 217 */
 218 int setup_myself(void)
 219 {
 220   config_t *cfg;
 221   subnet_t *subnet;
 222   char *name, *hostname, *mode, *afname, *cipher, *digest;
 223   struct addrinfo hint, *ai, *aip;
 224   int choice, err, sock;
 225 cp
 226   myself = new_node();
 227   myself->connection = new_connection();
 228   init_configuration(&myself->connection->config_tree);
 229
 230   asprintf(&myself->hostname, _("MYSELF"));
 231   asprintf(&myself->connection->hostname, _("MYSELF"));
 232
 233   myself->connection->options = 0;
 234   myself->connection->protocol_version = PROT_CURRENT;
 235
 236   if(!get_config_string(lookup_config(config_tree, "Name"), &name)) /* Not acceptable */
 237     {
 238       syslog(LOG_ERR, _("Name for tinc daemon required!"));
 239       return -1;
 240     }
 241
 242   if(check_id(name))
 243     {
 244       syslog(LOG_ERR, _("Invalid name for myself!"));
 245       free(name);
 246       return -1;
 247     }
 248
 249   myself->name = name;
 250   myself->connection->name = xstrdup(name);
 251
 252 cp
 253   if(read_rsa_private_key())
 254     return -1;
 255
 256   if(read_connection_config(myself->connection))
 257     {
 258       syslog(LOG_ERR, _("Cannot open host configuration file for myself!"));
 259       return -1;
 260     }
 261
 262   if(read_rsa_public_key(myself->connection))
 263     return -1;
 264 cp
 265
 266   if(check_rsa_key(myself->connection->rsa_key))
 267     {
 268       syslog(LOG_ERR, _("Invalid public/private keypair!"));
 269       return -1;
 270     }
 271
 272   if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 273     asprintf(&myport, "655");
 274
 275 /* Read in all the subnets specified in the host configuration file */
 276
 277   cfg = lookup_config(myself->connection->config_tree, "Subnet");
 278
 279   while(cfg)
 280     {
 281       if(!get_config_subnet(cfg, &subnet))
 282         return -1;
 283
 284       subnet_add(myself, subnet);
 285
 286       cfg = lookup_config_next(myself->connection->config_tree, cfg);
 287     }
 288
 289 cp
 290   /* Check some options */
 291
 292   if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
 293     if(choice)
 294       myself->options |= OPTION_INDIRECT;
 295
 296   if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
 297     if(choice)
 298       myself->options |= OPTION_TCPONLY;
 299
 300   if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice))
 301     if(choice)
 302       myself->options |= OPTION_INDIRECT;
 303
 304   if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
 305     if(choice)
 306       myself->options |= OPTION_TCPONLY;
 307
 308   if(myself->options & OPTION_TCPONLY)
 309     myself->options |= OPTION_INDIRECT;
 310
 311   if(get_config_string(lookup_config(config_tree, "Mode"), &mode))
 312     {
 313       if(!strcasecmp(mode, "router"))
 314         routing_mode = RMODE_ROUTER;
 315       else if (!strcasecmp(mode, "switch"))
 316         routing_mode = RMODE_SWITCH;
 317       else if (!strcasecmp(mode, "hub"))
 318         routing_mode = RMODE_HUB;
 319       else
 320         {
 321           syslog(LOG_ERR, _("Invalid routing mode!"));
 322           return -1;
 323         }
 324       free(mode);
 325     }
 326   else
 327     routing_mode = RMODE_ROUTER;
 328
 329   if(get_config_int(lookup_config(myself->connection->config_tree, "MaxTimeout"), &maxtimeout))
 330     {
 331       if(maxtimeout <= 0)
 332         {
 333           syslog(LOG_ERR, _("Bogus maximum timeout!"));
 334           return -1;
 335         }
 336     }
 337   else
 338     maxtimeout = 900;
 339
 340   if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname))
 341     {
 342       if(!strcasecmp(afname, "IPv4"))
 343         addressfamily = AF_INET;
 344       else if (!strcasecmp(afname, "IPv6"))
 345         addressfamily = AF_INET6;
 346       else if (!strcasecmp(afname, "any"))
 347         addressfamily = AF_UNSPEC;
 348       else
 349         {
 350           syslog(LOG_ERR, _("Invalid address family!"));
 351           return -1;
 352         }
 353       free(afname);
 354     }
 355   else
 356     addressfamily = AF_INET;
 357
 358   get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 359 cp
 360   /* Generate packet encryption key */
 361
 362   if(get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher))
 363     {
 364       if(!strcasecmp(cipher, "none"))
 365         {
 366           myself->cipher = NULL;
 367         }
 368       else
 369         {
 370           if(!(myself->cipher = EVP_get_cipherbyname(cipher)))
 371             {
 372               syslog(LOG_ERR, _("Unrecognized cipher type!"));
 373               return -1;
 374             }
 375         }
 376     }
 377   else
 378     myself->cipher = EVP_bf_cbc();
 379
 380   if(myself->cipher)
 381     myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 382   else
 383     myself->keylength = 1;
 384
 385   myself->connection->outcipher = EVP_bf_ofb();
 386
 387   myself->key = (char *)xmalloc(myself->keylength);
 388   RAND_pseudo_bytes(myself->key, myself->keylength);
 389
 390   if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 391     keylifetime = 3600;
 392
 393   keyexpires = time(NULL) + keylifetime;
 394
 395   /* Check if we want to use message authentication codes... */
 396
 397   if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest))
 398     {
 399       if(!strcasecmp(digest, "none"))
 400         {
 401           myself->digest = NULL;
 402         }
 403       else
 404         {
 405           if(!(myself->digest = EVP_get_digestbyname(digest)))
 406             {
 407               syslog(LOG_ERR, _("Unrecognized digest type!"));
 408               return -1;
 409             }
 410         }
 411     }
 412   else
 413     myself->digest = EVP_sha1();
 414
 415   myself->connection->outdigest = EVP_sha1();
 416
 417   if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->maclength))
 418     {
 419       if(myself->digest)
 420         {
 421           if(myself->maclength > myself->digest->md_size)
 422             {
 423               syslog(LOG_ERR, _("MAC length exceeds size of digest!"));
 424               return -1;
 425             }
 426           else if (myself->maclength < 0)
 427             {
 428               syslog(LOG_ERR, _("Bogus MAC length!"));
 429               return -1;
 430             }
 431         }
 432     }
 433   else
 434     myself->maclength = 4;
 435
 436   myself->connection->outmaclength = 0;
 437
 438   /* Compression */
 439
 440   if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->compression))
 441     {
 442       if(myself->compression < 0 || myself->compression > 9)
 443         {
 444           syslog(LOG_ERR, _("Bogus compression level!"));
 445           return -1;
 446         }
 447     }
 448   else
 449     myself->compression = 0;
 450
 451   myself->connection->outcompression = 0;
 452 cp
 453   /* Done */
 454
 455   myself->nexthop = myself;
 456   myself->via = myself;
 457   myself->status.active = 1;
 458   node_add(myself);
 459
 460   graph();
 461
 462 cp
 463   /* Open sockets */
 464
 465   memset(&hint, 0, sizeof(hint));
 466
 467   hint.ai_family = addressfamily;
 468   hint.ai_socktype = SOCK_STREAM;
 469   hint.ai_protocol = IPPROTO_TCP;
 470   hint.ai_flags = AI_PASSIVE;
 471
 472   if((err = getaddrinfo(NULL, myport, &hint, &ai)) || !ai)
 473     {
 474       syslog(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(err));
 475       return -1;
 476     }
 477
 478   tcp_sockets = 0;
 479
 480   for(aip = ai; aip; aip = aip->ai_next)
 481     {
 482       if((sock = setup_listen_socket((sockaddr_t *)aip->ai_addr)) < 0)
 483         continue;
 484
 485       tcp_socket[++tcp_sockets] = sock;
 486       if(debug_lvl >= DEBUG_CONNECTIONS)
 487         {
 488           hostname = sockaddr2hostname((sockaddr_t *)aip->ai_addr);
 489           syslog(LOG_NOTICE, _("Listening on %s/tcp"), hostname);
 490           free(hostname);
 491         }
 492     }
 493
 494   freeaddrinfo(ai);
 495
 496   hint.ai_socktype = SOCK_DGRAM;
 497   hint.ai_protocol = IPPROTO_UDP;
 498
 499   if((err = getaddrinfo(NULL, myport, &hint, &ai)) || !ai)
 500     {
 501       syslog(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(err));
 502       return -1;
 503     }
 504
 505   udp_sockets = 0;
 506
 507   for(aip = ai; aip; aip = aip->ai_next)
 508     {
 509       if((sock = setup_vpn_in_socket((sockaddr_t *)aip->ai_addr)) < 0)
 510         continue;
 511
 512       udp_socket[++udp_sockets] = sock;
 513       if(debug_lvl >= DEBUG_CONNECTIONS)
 514         {
 515           hostname = sockaddr2hostname((sockaddr_t *)aip->ai_addr);
 516           syslog(LOG_NOTICE, _("Listening on %s/udp"), hostname);
 517           free(hostname);
 518         }
 519     }
 520
 521   freeaddrinfo(ai);
 522
 523   syslog(LOG_NOTICE, _("Ready"));
 524 cp
 525   return 0;
 526 }
 527
 528 /*
 529   setup all initial network connections
 530 */
 531 int setup_network_connections(void)
 532 {
 533 cp
 534   init_connections();
 535   init_subnets();
 536   init_nodes();
 537   init_edges();
 538   init_events();
 539
 540   if(get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 541     {
 542       if(pingtimeout < 1)
 543         {
 544           pingtimeout = 86400;
 545         }
 546     }
 547   else
 548     pingtimeout = 60;
 549
 550   if(setup_device() < 0)
 551     return -1;
 552
 553   /* Run tinc-up script to further initialize the tap interface */
 554   execute_script("tinc-up");
 555
 556   if(setup_myself() < 0)
 557     return -1;
 558
 559   try_outgoing_connections();
 560 cp
 561   return 0;
 562 }
 563
 564 /*
 565   close all open network connections
 566 */
 567 void close_network_connections(void)
 568 {
 569   avl_node_t *node, *next;
 570   connection_t *c;
 571   int i;
 572 cp
 573   for(node = connection_tree->head; node; node = next)
 574     {
 575       next = node->next;
 576       c = (connection_t *)node->data;
 577       if(c->outgoing)
 578         free(c->outgoing->name), free(c->outgoing);
 579       terminate_connection(c, 0);
 580     }
 581
 582   if(myself && myself->connection)
 583     terminate_connection(myself->connection, 0);
 584
 585   for(i = 0; i < udp_sockets; i++)
 586     close(udp_socket[i]);
 587   for(i = 0; i < tcp_sockets; i++)
 588     close(tcp_socket[i]);
 589
 590   exit_events();
 591   exit_edges();
 592   exit_subnets();
 593   exit_nodes();
 594   exit_connections();
 595
 596   execute_script("tinc-down");
 597
 598   close_device();
 599 cp
 600   return;
 601 }